26Q THE PHYSIOLOGY OF REPRODUCTION 



2nd and 3rd lumbar nerves, and in the cat, the 3rd and 4th 

 lumbars, contained motor fibres for the vasa deferentia. The 

 fibres giving this result could be found outside the spinal cord 

 in the genito-crural nerve. The contraction of the vasa was 

 of a slow and peristaltic kind, and did not cease immediately 

 the stimulus was withdrawn.^ 



Langley and Anderson, as a result of an extensive series of 

 experiments, conclude that the internal generative organs of the 

 cat and rabbit are supphed by fibres running out by the anterior 

 roots of the 3rd, 4th, and 5th lumbar nerves, and sometimes 

 also the 2nd. These fibres pass through the sympathetic to the 

 inferior mesenteric gangUa, and continue their course by the 

 hypogastric nerves. Stimulation of these fibres in the cat and 

 the rabbit caused strong contraction of the whole musculature 

 of the vasa deferentia and uterus mascuhnus (which Langley 

 and Anderson regard as the physiological homologue of the 

 vesiculae seminales in these animals). The vas deferens in con- 

 tracting was observed to become from one to three centimetres 

 shorter, so that there could be no doubt that the longitudinal 

 muscular coat took part in the process. The contraction was 

 strong enough to cause emission of semen from the aperture of 

 the penis. It would appear, therefore, that ejaculation occurred 

 without erection. In the dog, in which the longitudinal muscle 

 layer is not well developed, the contraction of the vas deferens, 

 on excitation of the upper lumbar nerves, was not nearly so 

 pronounced. 



Langley and Anderson found that stimulation of the sacral 

 nerves had no effect on the internal generative organs. These 



1 There has been some disagreement as to whether the vas deferens under- 

 goes true peristaltic movement. According to Budge (toe. cit. ) this does occur 

 in the rabbit and cat. Fick confirmed Budge for these animals (" Ueber das 

 Vas deferens," Mailer's Archiv, 1856), but found no peristalsis in the dog 

 {cf. Langley and Anderson for the dog). On the other hand, Loeb (toe. cit.) 

 could discern no peristaltic movement in the vas deferens of the rabbit, 

 but only a powerful contraction. Nagel, who has more recently investigated 

 the question, states that the vas deferens in the rabbit does not undergo a. 

 true peristaltic movement, but a simple quick contraction which suffices for 

 the emptying the tube (" Contractilitat und Rarzburkeit des Samenleiters," 

 Verhandl. d. Phya. Qesell. zu Berlin ; Arch.f. Anat. u. Phys., Phys. Abth., 

 1905, Suppl. See also Nagel, Handbuch der Phys. des Menschen, vol. ii., 

 Braunschweig, 1906). 



